Electric ice cap



Feb. 7, 1933. Q 5;` HASSELL 1,896,953

ELECTRIC ICE CAP Filed May 18, 1931 A TTORNE Y.

Patented Feb. 7, 1.933

UNITED STATES PATENT oFi-plcE ELECTRIC ICE CAP Application illed lay 18,

This invention relates to thermal applicators for making hot or cold applications to the body in medical treatment.

An object of the invention is to provide electrical and mechanical means for producing a continuous supply of hot or cold fluid and for circulating t e fluid through a pad r cap applied to the body, by means of flexible tubes lor hose.

Another object is to provide means for automatic control of the temperature of the circulating fluid, which is adjustable to -any desired degree of temperature above or below body temperature.

Another object is to provide such a mechanism in small and compact form, which can be moved easily from room to room and can be rolled under a hospital cot while in use, or to dispose of it. f

In the accompanying drawing one form of mechanism suitable for this purpose is shown, in which: y

Figure 1 is the complete assembly, partly in side elevation, partly in section, and partly diagrammatic a Figure 2 is a sectional View of pad 4 with its tubes 6, shown and indicated in Figure 1; and

Figure 3 is a diagram of the electric circuits, laid out to correspond to the position of the mechanical parts in Figure 1.

The same reference numerals are used with corresponding parts in the different figures.

Pads may be of various form for a plication to different parts of the body. ne of my preferred constructions for the pad consists of two sheets or faces of rubber or other suitable flexible material, Figure 1, attached together at their edges 5, as in Figure 2, to form an oblong sack. Enclosed between faces 4 are bends of rubber tubing 6, which terminate in metal inlet and outlet nipples 7 and 8.

A filler opening and seal cap 9 may be provided, through which the sack may be filled with water or other liquid. Tubes 6 may be cemented or vulcanized at man points to the faces, but should not be continuously attached. If attached in spots, means will be rovided allowing for the li uid in the sacli) to seep past the tubes and fil the whole 1981. Serial No. 538,383.

sack, immersing the tubes in the liquid bath. Hot or cold liquid traversing the tubes then, will impart its temperature to the bath, the heat transfer between pad and the body of the patient being facilitated.

A small cabinet 10 on casters 11 contains the mechanism for maintaining the sup ly of hot or cold fluid circulating through tu 6. In the cabinet, a small motor 12 drives compressor 13, sending a suitable refrigerant 6 gas under pressure through cooling element 14. Fan 15 on the compressor shaft ventilates the cooling element, reducing the gas to liquid. The liquid passes adjustable expansion valve 16 into expansion coil 17, con- 55 tained in tank 18, where it returns to gas by taking up heat from the fluid in the tank. The compressor receives the gas again from coill 17 and recompresses it, to repeat the cyc e.

The centrifugal circulator 19 on the motor shaft draws the cooled liquid from tank 18 through pipe 20 and forces it'through pipe 21, flexible hose 22, tubing 6, return ,hose 23 and pipe 24 back to tank 18, extracting heat 75 from the bath in pad 4 durin its passage. Power for motor 12 is obtaine by inserting plug 25 in any convenient outlet. The electric circuits will be described below.

eans for automatic control of temperature of the fluid in tank 18, being circulated through pad 4, is provided. A leaf 26 of thermostatic metal is secured at the bottom of well 27, with its upper end free and adapted to tilt mercury switch 28, Figurel. InFigure 3, switch 28 is seen in the circuit diagram. The switch box extends through the top of cabinet 10 and has 'a dial 29, which may be marked with degrees of temperature. The stem of the dial carries a brush 30, which bears on circular bar 31 when the dial is turned to the left. In this position, the circuit is closed through solenoid 32, as understood from Figure 3, provided switch 28 is aired to the left. l 9

Any suitable magnetic clutch may be employed to connect compressor 13 to motor 12. As here shown, a balanced thrust cone clutch 33 is actuated by the iron bound solenoid 32. When manual switch 34 is closed, motor 10 12 is set in motion and operation continues until switch 34 is manually opened, circulating the fluid in tank 1 8 through1 pad 4. Ad-

]ustable thermostats are well 5 particular construction is not shownwhich 28 to open position and releases clutch 33.

The tilting of switch 28 by leaf 26 maintains the circulating fluid at nearly constant temperature in pad 4. Adjustment means may be provided for making easy correction of errors in the thermostat.

Should a hot application be desired, dial 29 is turned to the right to the calibration indicating the desired temperature. Brush 30 now makes contact with bar 35, permanently breaking the circuit through clutch 33 and closing the circuit through an electric heating element 36, provided mercury switch 37 is tilted to the right, as understood from Figure 3. The two mercury switches 28 and 37 are mounted side by side on the same pivot, so that only one is seen in Figure 1. The single thermostat leaf 26 then serves to actuate-both switches, the pivot on which they tilt being shifted to right or left by the turning of dial 29 to determine the temperature a which the leaf shall tilt them over. With the dial to the right, the refrigeration system remains permanently out of operation, while current is switched through heating element 36 whenever the circulating fluid falls below the intended temperature, maintaining a continuous supply of hot fluid throughfpad 4 at nearly constant temperature.

Tank 18 may be insulated, las shown, to conserve the temperature induced in the fluid. A filler opening on top of tank 18 is provided, as shown, for supplying water, brine or other circulating fluid. 'With motor 12 running, the fluid will fill the hose and tubes 6.

In this manner, a compact mechanism is enclosed in a small cabinet, on top of which the pad, hose and power cord may be coiled, which can be stowed in small space, drawn from room to room, or rolled under a cot while in operation. The invention is not intended to be limited, however, to the construction or any of the details shown or described, but is intended to embrace the scope of the following claims.v

own and the4 ly driven motor for driving the pump; a mechanical refrigerator for cooling such fluid in the container; a magnetic clutch adapted to connect the refrigerator to the motor; and a thermostat exposed to the circulating fluid. controllingv the electric circuit through the magnetic clutch;

2. A thermal applicator comprising a holow pad having an inlet and an outlet for circulation of liquid, a liquid container havmg an inlet and an-outlet, tubes connecting the container outlet and inlet with the pad inlet and outlet, respectively, constantly operated means for causing the liquid to circulate through the circuit thus provided, and means in the container for automatically maintaining the liquid therein at a predetermined temperature.

3. A thermal applicator comprising a hollow pad having an inlet and an outlet for circulation of liquid, a liquid container having an outlet and an inlet, tubes connecting the container outlet and inletv with the pad inlet and outlet, respectively, constantly operated means for causing circulation of the liquid through the circuit so provided, and means operated by variations in temperature of the liquid for maintaining said liquid substantially at any desired temperature.

In testimony whereof I aiiix my signature.

CECIL STARKE HASSELL. 

